1 //===----------------------------------------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 // <string_view>
10 
11 // [string.view.capacity], capacity
12 // constexpr size_type size()     const noexcept;
13 // constexpr size_type length()   const noexcept;
14 // constexpr size_type max_size() const noexcept;
15 // constexpr bool empty()         const noexcept;
16 
17 #include <string_view>
18 #include <cassert>
19 #include <limits>
20 
21 #include "test_macros.h"
22 
23 template<typename SV>
24 void test1 () {
25 #if TEST_STD_VER > 11
26     {
27     constexpr SV sv1;
28     static_assert ( sv1.size() == 0, "" );
29     static_assert ( sv1.empty(), "");
30     static_assert ( sv1.size() == sv1.length(), "" );
31     static_assert ( sv1.max_size() > sv1.size(), "");
32     }
33 #endif
34 
35     {
36     SV sv1;
37     ASSERT_NOEXCEPT(sv1.size());
38     ASSERT_NOEXCEPT(sv1.empty());
39     ASSERT_NOEXCEPT(sv1.max_size());
40     ASSERT_NOEXCEPT(sv1.length());
41     assert ( sv1.size() == 0 );
42     assert ( sv1.empty());
43     assert ( sv1.size() == sv1.length());
44     assert ( sv1.max_size() > sv1.size());
45     }
46 
47     // Sanity check max_size() -- a string_view can't store more bytes than a single object
48     // can contain. Any implementation that fails this check is certainly lying.
49     {
50         typedef typename SV::value_type CharT;
51         typedef typename SV::size_type Size;
52         SV sv;
53         assert(sv.max_size() <= std::numeric_limits<Size>::max() / sizeof(CharT));
54         LIBCPP_ASSERT(sv.max_size() == std::numeric_limits<Size>::max() / sizeof(CharT));
55     }
56 }
57 
58 template<typename CharT>
59 void test2 ( const CharT *s, size_t len ) {
60     {
61     std::basic_string_view<CharT> sv1 ( s );
62     assert ( sv1.size() == len );
63     assert ( sv1.data() == s );
64     assert ( sv1.empty() == (len == 0));
65     assert ( sv1.size() == sv1.length());
66     assert ( sv1.max_size() > sv1.size());
67 #if TEST_STD_VER > 14
68 //  make sure we pick up std::size, too!
69     assert ( sv1.size() == std::size(sv1));
70     assert ( sv1.empty() == std::empty(sv1));
71 #endif
72     }
73 }
74 
75 int main(int, char**) {
76     test1<std::string_view> ();
77 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
78     test1<std::u8string_view> ();
79 #endif
80     test1<std::u16string_view> ();
81     test1<std::u32string_view> ();
82 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
83     test1<std::wstring_view> ();
84 #endif
85 
86     test2 ( "ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
87     test2 ( "ABCDE", 5 );
88     test2 ( "a", 1 );
89     test2 ( "", 0 );
90 
91 #ifndef TEST_HAS_NO_WIDE_CHARACTERS
92     test2 ( L"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
93     test2 ( L"ABCDE", 5 );
94     test2 ( L"a", 1 );
95     test2 ( L"", 0 );
96 #endif
97 
98 #if defined(__cpp_lib_char8_t) && __cpp_lib_char8_t >= 201811L
99     test2 ( u8"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
100     test2 ( u8"ABCDE", 5 );
101     test2 ( u8"a", 1 );
102     test2 ( u8"", 0 );
103 #endif
104 
105 #if TEST_STD_VER >= 11
106     test2 ( u"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
107     test2 ( u"ABCDE", 5 );
108     test2 ( u"a", 1 );
109     test2 ( u"", 0 );
110 
111     test2 ( U"ABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDEABCDE", 105 );
112     test2 ( U"ABCDE", 5 );
113     test2 ( U"a", 1 );
114     test2 ( U"", 0 );
115 #endif
116 
117   return 0;
118 }
119